Book a Glaucoma Test Before Year End, Says Dr. T Fletcher

Most people with glaucoma have no idea they have it. The most common form brings no pain and no early change in eyesight, and it can quietly erode the optic nerve for years before anything seems wrong, which is why it has earned the nickname "the silent thief of sight". Dr. Taryn Fletcher, an ophthalmic surgeon based in Bryanston, Johannesburg, is urging adults who have gone a while without a full eye examination to have one before the year ends, especially those in a higher-risk group.

November is a good time to do it. Plenty of people clear their backlog of postponed health appointments in the weeks leading up to the December break. Eye examinations tend to slip off that list, because glaucoma rarely gives anyone a reason to book one.

How glaucoma harms the eye

The disease attacks the optic nerve, a bundle of more than a million fine nerve fibres that relays signals from the eye to the brain. In most cases the trouble starts with fluid collecting in the front of the eye. Normally this fluid escapes through the drainage angle, which keeps the pressure inside the eye steady. If that angle stops working as it should, pressure climbs and the nerve begins to suffer.

Each nerve fibre that dies leaves a gap, and blind spots form in the field of vision. These typically appear first around the edges, so many people only become aware of them once a large portion of the optic nerve is already gone. Glaucoma ranks among the leading causes of blindness in people over 60, but early treatment can often prevent that outcome. Lost nerve tissue cannot be restored, so catching the disease early is what counts.

The two main forms

Primary open-angle glaucoma is the type most people have. It progresses slowly, much like a drain that gradually clogs, without pain and without any early shift in vision. Certain people have optic nerves that are vulnerable even when eye pressure is normal, which adds to their risk.

Angle-closure glaucoma occurs when the iris lies very near the drainage angle and can obstruct it. A complete blockage makes pressure spike rapidly, an event known as an acute attack and a genuine eye emergency. The signs to watch for are sudden blurred vision, severe pain in the eye, headache, nausea or vomiting, and rainbow-coloured rings or halos around lights. Anyone experiencing these should get in touch with an ophthalmologist straight away. This type can also creep up slowly and silently until the damage is advanced.

Who needs an examination

Certain groups carry a greater than average risk. The patient information supplied by Dr. Fletcher's practice lists people over 40, those with relatives who have glaucoma, people of African or Hispanic heritage, anyone with high eye pressure, people who are farsighted or nearsighted, those who have had an eye injury, people whose corneas are thin in the centre, and those with diabetes, migraines, poor circulation or other conditions affecting the whole body. Having several of these factors raises the risk further still.

In a city with Johannesburg's diversity, a large proportion of adults fit at least one of those descriptions. Talking through personal risk with an ophthalmologist in Johannesburg is the first step in working out how frequently an examination should be done.

Why measuring pressure is not enough

The practice is clear that a screening which looks only at eye pressure will not reliably detect glaucoma. A complete eye examination is the only definite way to diagnose it. That examination covers measuring eye pressure, checking the drainage angle, looking at the optic nerve for damage, testing peripheral vision, photographing or digitally measuring the optic nerve, and measuring corneal thickness.

Combined, these results reveal whether glaucoma is present, how advanced it is and how urgently treatment should begin. Carrying out and interpreting this kind of assessment is exactly what ophthalmologists are trained for.

Treatment options

Most glaucoma is managed with eye drops used every day to bring down the pressure inside the eye, either by cutting the amount of fluid produced or by improving drainage. Laser procedures and surgery are other ways of helping fluid flow out. Whatever the method, the goal is to prevent further damage.

Because eye drops can cause side effects, patients are advised to share a complete list of their medicines with their doctor, never to stop or alter glaucoma medication without first consulting their ophthalmologist, and to request refills before they run out. Dr. Fletcher has also written about how glaucoma and dry eye are connected, since many glaucoma patients have both. Preservatives in some drops can irritate the eye's surface, and switching to preservative-free drops can relieve symptoms for some people. Air conditioning and long stretches in front of a screen, both typical of office life in summer, can aggravate dry eye.

Symptoms that need prompt attention

Glaucoma may be quiet, but the practice also points out symptoms that should never be ignored. A sudden burst of new floaters, particularly alongside flashes of light, may mean the gel inside the eye is separating from the retina, and sometimes that the retina is tearing or detaching. Anyone who experiences this, even while on holiday, should get medical help immediately. Reaching an ophthalmologist fast in that situation can have a real effect on the result.

About the practice

Dr. Fletcher's areas of focus are microincision cataract surgery, glaucoma, medical retinal disease and aesthetic ophthalmology. She graduated in medicine from the University of the Witwatersrand in 2005, served as a medical officer at St John Eye in 2008 and qualified as an ophthalmologist in 2013. After a period as an honorary consultant at Helen Joseph Hospital, she opened her own practice in 2014. She is a member of the Ophthalmological Society of South Africa, the European Glaucoma Society and the European Society of Cataract and Refractive Surgeons.

Consulting hours are Monday to Friday, 8:00 to 17:00. To book a glaucoma assessment before year end, or to read more about the conditions the practice treats, visit https://drtfletcher.co.za/.

About Dr. T Fletcher

Dr. Taryn Fletcher is an ophthalmic surgeon in private practice at Bryanston Place Office Park, 199 Bryanston Drive, Bryanston, Johannesburg. The practice focuses on microincision cataract surgery, medical retinal disease and aesthetic ophthalmology, and also treats glaucoma, age-related macular degeneration, pterygium and flashes and floaters.